field sandbur vs sandspur

field sandbur and sandspur both are nouns.

Word	Noun	Adjective	Verb	Adverb
field sandbur	Yes	No	No	No
sandspur	Yes	No	No	No

As nouns, field sandbur and sandspur are synonyms defined as:

field sandbur and sandspur: grass of the eastern United States and tropical America having spikelets enclosed in prickly burs

Other synonyms of field sandbur include Cenchrus tribuloides, sandbur.

field sandbur (noun)	sandspur (noun)
grass of the eastern United States and tropical America having spikelets enclosed in prickly burs	grass of the eastern United States and tropical America having spikelets enclosed in prickly burs